If it is not removed, you continue gaining health, and when combined with buffs or for instance Righteous Protector it's very likely you'll gain at least 6 health from a 3 mana minion.

Additionally, more synergy to Blackguard, a card I'd like to play more but never seemed to be that effective. A solid 3 damage to a minion seems like it will give you a similar board stance as Despicable Dreadlord, as your opponent has to remove it or else it will continue chipping away at their minions.

What Paladin needs to have a control archetype is card-draw, not health restoration. Paladin already has all the healing they would need and a perfect win condition in the form of Uther of the Ebonblade. But with only Divine Favor as their draw, which doesn't work in a control deck, they are fucked. We need a new Solemn Vigil or something to that effect to revive the control Paladin dream.

Not earth shattering, but not terrible either. It could make for a decent backup behind Wickerflame Burnbristle against any other shielded minions since lifesteal doesn't heal when hitting a divine shield.